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UNITED STATESv PETEN-T., Ginn-CE1.A

'STEWART D. McKELvEY, OE" CANTON, OHIO, 'AssicNOR -OE'ONE-T'H'IRD To JOSEPH A. LINvILLE, OF SAME. PLACE.

TELEPHONE;

SPECIFICA/.5210K formingpart of Letters PatentNo. 517,762, dated April 3, 1894.

Application filed February 20, 1893. Serial No. 463,130. (No model.) l

To all whom t .may concern.- Y

Be itkn'own that I, STEWART D. McKELvEY, a citizenof-the United States, residing at Can: ton, in the county of Stark and State of Ohio, have invented new and useful Improvements in Telephones, 4of whichk the following is a specification, y x f' Myinvention relates to telephones, and the purpose thereof is to dispense with that type of transmitter which receives pulsations directlyzffroin the mouth of the speaker, and to substitute a transmitter which shall be -responsive to the vibrations generated in the muscular tissues by the phonetic pulsations, or vibrations, produced kby the vibrations of the larynx, the transmitter being capable of y attachment to` any ordinary chair and-to any convenient part of the said chair in which the person using the telephone sits.

' It is a further purpose 0f my invention tov provide a simple and economical structure, whereby the transmitter may be so placed and attached as to respond to the phonetic vibrations of the body -of the speaker, who may stand or, if preferred, sit in any suitable chair, having a suitable and convenient support for -the back.

part of a chair, or other seat,- in which thev person using the telephone sits, suitable means being provided for the attachment of the phone.

To these ends, myinvention consists in the severalnovel features of construction and in the new combinations of parts hereinafter fully set forth and then more particularly described and definitely pointed out in. the claims following this specification.

l To enableothers skilled in the art to make,

construct and use my said invention I will now proceed to describe` the saine in det-ail,

ofthe back ofthe chair shown in Fig.1, showing the attached phone, and also showing in diagram the circuit connections. 'Y

' In the said drawings ,the reference-numeral l indicates a chair or seat of any ordinary pattern. To the rearward face of the back of said chair, or to a single flatv bar, or brace, forming part of said back, I attach a phone composed of a cylindrical body-portion 2, having suitably mounted thereon a diaphragm 3, of any preferred type. The cylindrical bodyportion is closed at one end by a cap-piece 4, rmly attached to theA chair by screws, orv in any other suitable manner,its iiange 5 fitting over, and being preferably connected thereto by a male and female thread, respectively.V The other end, which is most remote from the chair, receives a cap 6 which is attached in substantially the same manner. The cappiece 6, hasa flange 7 which surrounds the end of the cylinder 2. Thediaphragm 3 isl usually held in 2- Iis 8, which nts the Gyas-' The numeral 9 indicates the localbattery,'

from which a wire 10 is connected to a binding-post 12, which is properly insulated to have-electrical connection with the ring-support 8 of the diaphragm. This wire 10 connects the positive pole of the local battery 9 with the diaphragm-ring 8 by Way of the binding-post 12. From the opposite pole of the battery 9 a wire 13 is led to the primary of an induction-coi1 14. A wire 15, connected to the other terminal of the primary of said induction-coil 14,-is led to a binding-post V16, mounted upon the cylindrical body-portion 2. A'spring 17 of light tension, is in electrical contact with said binding-post 16, and extends radially, or substantially so, into the zo.l

body-portion 2,' so that its free extremity'm'ay IOO of the diaphragm 3, in such manner that the point 18 ofisaid spring 17 shallhave contact with the middle, or central portion 19, of the diaphragm, which is preferably a button ot carbon, attached to the face of the diaphragm, or it may be inserted in a central opening, or aperture, in the diaphragm. Ifwllstate, atl this point, that the induction-coil mayeasily be housed Within the cylindrical body-portion 2, by simply making the latter of slightly greater length. One terminal 2O of the secondary coil of the induction-coil 14 is connected to one terminal of the induction-coil having its spool mounted upon the permanent magnet, which is housed inthe handle of the receiver 21. The other terminal of said inductioncoiliis connected with the main line 22. The remaining terminall23, of the sec ondary of: the induction-coil14, is either connected to a metallic return-circuit, or to earth. The receiver 21 is suspendedfrom a hook 24, mounted upon the chair-seat, or any other. convenienti` part, t where it can readily 4be reached bya person sitting in a` cha'ir, and the construction and operation of the .parts may be such thatthe Weight of, the receiver will operate the hook insuch manner as to cut out-all the connections of the local instrument except the local battery 9..

The chair, stool, or other ordinary form of.; seat 1, is preferably placedf with each of its legs restinggupon a metallic plate 25, ofl any suitable form. These plates form parts of the line andlocal circuits, which are as follows: Beginning with the positive poleof the local battery 9, the Wire 13 is led to one terminal oftheprimary of the induction-coil 14; thence, fromtlie other terminal ot the primary, by Way of a Wire 15, to one of the metallic plates 25 which lies beneath one of the frontlegs, of the chair. From this plate said `Wire 15 passes upward, along the fore-leg of the chair, then around the edge of the seat to a point at, or near, `the central, or nearly central, longitudinal line of the back 1C, .from which point it is carriedupward and connected to the binding-post 16, on the cylindrical body-portion 2 of the transmitter attached to the back ofthe chair in Fig. 1. From the binding-postl, the current passes through spring 17, point 1S, central carbon-button 19 and diaphragm 3 to the binding-post 12 and` thence by wire 10 back to the other pole of the battery. In Fig. 1 the Wire 10 isshown as carrieddown- Ward fromthe binding-post 12 nearly in parallelism with thewire15,and is drawn through an eye 27 on the chairseat,.and around to,or

nearly to, one of the fore legs ot the chair,.

which is provided with a contact-terminalll resting. on a metallic` plate 25.` Each of the chairlegs is provided with a similar contactterminal which rests upon a similar metal plate 25. From this plate the Wire 10, electrically connected thereto, is carried to the other pole of the local battery, thus completing the local circuit. The main line circuit is by way of the Wire 22, which is carried to the receiver:

a plate 25 supporting one of the rear legs of the chair.y From thisplate, a wire22" is led to one of the binding-posts 28, upon the re ceiver 2l, thence through the induction-coil, upon the permanent magnet within said receiver, and to the other binding-post 22b on FromV this latter binding-post thewire20 is carriedlaround the rear of the seat, to the rear leg resting upon plate 1, and

is led down said leg to the plate last mentioned. From this plate a wire 2O:L is led to one terminal ot' the secondary of the induction-coil 14. 'lhe other terminal of the said secondary is connected to earth, or to a return metallic circuit.

It will readily be understood that the foregoing circuits arel simply those Which are showntin the organization bywhich` the inventionhis disclosed in;thisispecication, but that theseare subject to `aconsiderable variation without any departure Afromtheessential featuresof myinvention.

The induction-coil 14 may be placed.inor upon, a bracket on the wall, atanyconvenient oint. p Telephones ot.I this-` construction may be easily applied tosoundingrboardsot pianos, or to othervmusical' instruments or toa large sounding-board whichrreceives the pulsations producedbyan orchestraor band, or bythe voice of a public speaker.`

One especial advantage of; my present invention` resides in the fact` that vibrations producedby other `sources `than the Avoice of the person usingthe instrumentv are not received by the diaphragmuness the chair, or other support, is in contact, mechanically, with thesource of such` foreign vibrations. Thus, if apiano is played inthe same `room and at the time aimessage is received over the wire, the telephonie receiver does not respond in any audible degree, to the sound and the ear ofthe person listening to the message is notl confused.

What I. claimisv 1. In a telephone, a transmitter, a vibratory structure to which the transmitter box orhousing is rigidly attached,` said substance, or structure, being of such character that the speaker may support his body upon and againstthe same, and a suitable receiver, substantially as described.

2. In a telephone, `the combination with a chair, or means of supportd for the body of the speaker, of atransmitterthe housing of which is firmly attached to some part ot' said chair or other support upon and against which the body of the speaker rests andiasuitable receiver, substantiallyas described.

3. The combination with achair, orA other means of supportot ai. telephone i transmitter, rigidly attachedtoaportion otV the chairback, a receiver,.a local battery, and indue tion-coil having its-primary intcircuit with said battery throughra vibratingpoint acting upon the diaphragm, and a receiver having its induction-coil connected by one terminal IIO to the secondary of the induction-coil which is energized by the local battery and also connected by the other terminal tothe line, substantially as described.

4:. The combination with a chair, or other means of support of a transmitter consisting of a housing containing the diaphragm, said housing being rigidly attached to the back of the-chair, a receiver suspended by a hook arranged at the side of the seat, a local circuit including the diaphragm and its vibratory point-carrying arm, andv the primary of an induction-coil and a circuit for the sec-V.

ondary of the induction-coil,incuding the in- A duction-coil ofthe receiver andthe line-wire, substantially as described.

Y are placed,

said chair, and a circuit STEWART D. MCKELvEY.

Witnesses:

H. B. WEBBER,- H. E; McKELvEY. 

